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<html lang="en">

<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>

<body>

    <script>
        //1.创建xhr对象
        var xhr = new XMLHttpRequest();
        //2.调用open函数
        xhr.open("POST", "http://www.liulongbin.top:3006/api/addbook")
        //3.设置Content-Type属性 (必须放在open之后,send之前)
        xhr.setRequestHeader("Content-Type", "application/x-www-form-urlencoded")
        //4.调用send函数 并且发送请求数据(用查询字符串的方式提交数据)
        xhr.send("bookname=hellod&author=he&publisher=安徽")
        //5.监听onreadystatechange时间
        xhr.onreadystatechange = function () {
            if (xhr.readyState === 4 && xhr.status === 200) {
                console.log(xhr.responseText);
            }
        }

    </script>
</body>

</html>